code: def from_pandas(data, chunk_size=None, gpu=None, sparse=False):
      op = DataFrameDataSource(data=data, gpu=gpu, sparse=sparse)
      return op(data.shape, chunk_size=chunk_size)
  
file_path: mars/mars/dataframe/datasource/dataframe.py
imports: import itertools
  import pandas
  from ...None import opcodes
  from ...config import options
  from ...core import OutputType
  from ...serialization.serializables import DataFrameField, SeriesField
  from ...tensor.utils import get_chunk_slices
  from ...utils import estimate_pandas_size
  from ..utils import decide_dataframe_chunk_sizes, parse_index, is_cudf
  from ..operands import DataFrameOperand, DataFrameOperandMixin
label_desc: Use image node_id 1 for calling a global function with example usage: from_pandas(data, chunk_size, gpu, sparse) and returns: op